Drop Pan System and Sample Separator for Grain Loss Measurement or Other Sample Collection and Assessment

ABSTRACT

A drop pan system for collecting discharge samples from combine harvesters or other conveyed machines or implements features a support housing attachable to the machine, a drop pan receivable in a nested position within said housing, and a magnetic hold/release mechanism with electro-permanent magnets responsive to selective energization to switch from a holding state emitting an external magnetic field for holding the drop pan in the nested position, to a release state cancelling said external magnetic field to thereby release the drop pan from the housing. A power supply is positioned on the housing at an area that resides within a footprint of the drop pan&#39;s nested position. Differently sized drop pans are included, and the housing features alignment guides for self-aligning the selected pan during magnetically aided placement thereof. Electrical components of the housing are contained in an enclosure that doubles as a support for the electro-permanent magnets.

FIELD OF THE INVENTION

The present invention relates generally to drop pans releasably mountedto the undercarriage of a combine harvester or other conveyed machine orimplement for dropping of the pan to the ground to collect a sample ofthe material discharged from the rear outlet of the machine or implementas its drives forwardly past the dropped pan, and to devices forseparating components of the collected sample to assess operationalperformance of the machine.

BACKGROUND

Drop pans of the above described type have been used for the purpose ofevaluating grain losses during operation of the combine harvester. Toassess the loss, the drop pan is used to collect a sample of thedischarged straw and chaff from the combine harvester, which is theninspected for the presence of grain kernels that were not properlyseparated from the chaff during processing of the cut crop in within thecombine harvester. The quantity of usable grain kernels in the collectedsample relative to the sample size is used to gauge the effectiveness ofthe combine harvester's current performance. If the measured grain lossis beyond an acceptable threshold, adjustment to the operatingcharacteristics of the combine harvester to better suit the current cropconditions can be made to improve performance and reduce losses.

UK Patent Application GB2387098 discloses placement manual placement ofa drop pan, thus requiring increased personnel to enable manual dropplan placement relative to a moving combine harvester. This referencealso discloses a separator for separating the straw and chaff of thecollected sample from the lost grain kernels contained therein. Theseparator features a cylindrical container with a pervious mesh screensituated below an open upper end of the container, and a fan mountedbeneath the mesh screen to blow air upwardly therethrough. The collectedsample of the drop pan is poured into the separator, where the airflowblows the chaff and straw through the open end of the container, leavingthe grain kernels to settle atop the mesh screen.

U.S. Pat. No. 5,951,395 discloses a drop pan system in which anopenable/closeable housing is bolted to the undercarriage of the combineharvester to normally store the drop pan therein, until such time as arelease cable operated by the driver of the combine harvester opens thehousing to drop the pan to the ground, thus avoiding the need foradditional personnel.

Feiffer Consult (http://feiffer-consult.de) offers a drop pan system inwhich an open-bottomed housing bolted to the undercarriage of thecombine harvester has electromagnets that normally hold the drop pan ina nested position inside the housing, until power to the unit is cut offto drop the pan to the ground. The system lacks a dedicated powersource, instead having a power cable intended for connection to a cutterbar trolley plug found on some combine harvesters. This convenientlyruns the system off the vehicle's existing power supply, but renders thesystem incompatible with combine harvesters that lack such a plug.

German Utility Model DE202015000327 addresses this problem by insteadproviding a power supply on the magnetically attached housing, and alsoprovides a wireless handheld transmitter by which the electromagnets arede-energized in order to release the pan.

German Utility Model DE102016201413 omits the use of a separate housingto support the drop pan, and instead mounts a dedicated power supply andelectromagnetic components on the drop pan itself to enable directmagnetic attachment thereof to the undercarriage of the combineharvester.

Similar to the latter German reference, a commercially available systemmarketed under the name ScherGain (http://www.shergain.ca) magneticallymounts its drop pan directly to the combine, rather than via a separatehousing.

Despite the forgoing developments in the field of grain loss monitoring,there remains room for improved and alternative designs for grain lossdrop pans and sample separators.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a droppan system for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising:

a support housing attachable to the machine or implement;

a drop pan receivable in a nested position at least partially withinsaid housing;

a magnetic hold/release mechanism comprising at least oneelectro-permanent magnet responsive to selective energization to switchfrom a holding state emitting an external magnetic field for holding thedrop pan in the nested position, to a release state cancelling saidexternal magnetic field to thereby release the drop pan from thehousing;

a power supply supported on the housing;

a control circuit between the power supply and the magnetic hold/releasemechanism operable to make and break an electrically conductiveconnection therebetween; and

a remote control transmitter communicable with a receiver in the controlcircuit to effect switching of said control circuit from an open statein which the magnetic hold/release mechanism is de-energized, to aclosed state in which the magnetic/hold release mechanism is energized.

According to a second aspect of the invention, there is provided a droppan system for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising:

a housing attachable to the machine or implement;

a set of differently sized drop pans, each drop pan being selectivelyreceivable in a nested position at least partially within the housing;

a hold/release mechanism operable between a holding state holding thedrop pan in the nested position and a release state releasing the droppan from the housing; and

alignment guides for selectively aligning any selected one of saiddifferently sized drop pans relative to the housing and the hold/releasemechanism during nested placement of said selected one of saiddifferently sized drop pans in said housing.

According to a third aspect of the invention, there is provided a droppan system for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising:

a housing attachable to the machine or implement;

a drop pan selectively receivable in a nested position at leastpartially within the housing;

a magnetic hold/release mechanism operable between a holding stateholding the drop pan in the nested position and a release statereleasing the drop pan from the housing;

an enclosure that houses one or more electronic components for operatingthe hold-release mechanism, and that doubles as a support on whichmagnetic components of the magnetic hold/release mechanism aresupported.

According to a fourth aspect of the invention, there is provided a droppan system for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising:

a drop pan; and

a hold/release mechanism operable between a holding state holding thedrop pan in a carried position on the machine or implement and a releasestate releasing the drop pan from the machine or implement;

wherein said drop pan has a width of less than 8-inches.

According to a fifth aspect of the invention, there is provided a droppan system for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising:

a drop pan; and

a hold/release mechanism operable between a holding state holding thedrop pan in a carried position on the machine or implement and a releasestate releasing the drop pan from the machine or implement;

wherein said drop pan has a out-turned wings extending outwardly fromperimeter walls thereof.

According to a sixth aspect of the invention, there is provided a droppan system for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising:

a housing attachable to the machine or implement;

a drop pan selectively receivable in a nested position at leastpartially within the housing;

a magnetic hold/release mechanism operable between a holding stateholding the drop pan in the nested position and a release statereleasing the drop pan from the housing;

a power supply supported on the housing for powering the magnetichold/release mechanism, said power supply being positioned at an area ofsaid housing that resides within a footprint of the drop pan's nestedposition inside the housing.

According to a seventh aspect of the invention, there is provided agrain loss sample separator for separating grain kernels from straw andchaff in a grain loss sample, said grain sample separator comprising:

a screen atop for receiving said grain sample thereatop; and

a variable speed air moving device operable to force air upwardlythrough said screen to thereby blow away said straw and chaff whileleaving said grain kernels to settle atop the screen; and

an airflow control mechanism having multiple air speed settingsselectable by a user to adjust an airflow speed through said screenaccording to crop characteristics of said grain loss sample.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will now be described inconjunction with the accompanying drawings in which:

FIG. 1 is an exploded bottom perspective view of a drop pan system ofthe present invention.

FIG. 2 is an exploded top perspective view of the drop pan system ofFIG. 1.

FIG. 3 is a bottom plan view of a support housing of the drop pansystem.

FIG. 4 is a cross-sectional view of the support housing of FIG. 3, asviewed along line A-A thereof.

FIG. 5 is a schematic elevational view illustrating the drop pan systemin an installed position on the underside of an axle housing of acombine harvester's undercarriage.

FIG. 6 is an end view of the larger drop pan of the drop pan system ofFIG. 1.

FIG. 7 is a perspective view of a grain loss sample separator of thepresent invention.

FIG. 8 is an overhead plan view of the grain loss sample separator ofFIG. 7.

FIG. 9 is an elevational view of the grain loss sample separator of FIG.7.

FIG. 10 is a cross-sectional view of the grain loss sample separator ofFIG. 8 as viewed along line B-B thereof.

DETAILED DESCRIPTION

FIGS. 1 and 2 illustrate exploded views of a drop pan system 10 of thepresent invention, which features a support housing 12 magneticallymountable to the undercarriage of a combine harvester to releasablycarry a drop pan thereunder. The illustrated embodiment features twodifferent sized drop pans 14A, 14B each selectively receivable by thesupport housing 12 to support the selected drop pan beneath the combineharvester. The user can select between the two differently sized pansaccording to different crop conditions, as described in more detailfurther below.

The support housing features a rectangular top wall 16, and a set offour peripheral walls depending downward therefrom at respectiveperimeter edges of the top wall 16. Of these four peripheral walls,front and rear housing walls 18 extend longitudinally of the rectangulartop wall, and are longer than left and right housing walls 20 thatinterconnect the front and rear housing walls at the opposing endsthereof. The housing 12 has an open bottom of rectangular shapedelimited by the lower ends of the peripheral walls in a lower plane ofthe housing that resides oppositely of the top wall 16 in parallelrelation thereto. The space bound between the top wall and lower planewithin the confines of the peripheral walls denotes an interior space 22of the housing, which is thus closed off at the top and on all fourperipheral sides, but is open at the bottom. The housing thus forms aninternally hollow, open-bottomed, rectangular parallelepiped.

The interior space 22 of the support housing 12 features an elongatedcentral enclosure 24 running longitudinally of the housing in parallelrelation to the front and rear walls 18 at a longitudinal mid-plane Plocated centrally therebetween. Walls of this enclosure 24 are definedby a length of square channel attached to the underside of the housing'stop wall. Front and rear enclosure walls 26 run parallel to the frontand rear housing walls 18 in parallel relation thereto on respectivesides of the longitudinal mid-plane P. A bottom enclosure wall 28 spansbetween the front and rear enclosure walls 26 at lower ends thereof inspaced and parallel relation to both the top wall 16 and lower plane ofthe housing 12, whereby the bottom wall 28 of the enclosure 24 resideswithin the interior space 22 of the housing 12 at an intermediateelevation between the top wall 16 and open bottom thereof.

Electronic components of the support housing 12 are contained within theenclosure 24 between the front and rear enclosure walls 26 and betweenthe top housing wall 16 and the bottom enclosure wall 28. Theseelectronic components include a power supply 30 containing or consistingof one or more rechargeable batteries, and a control module 32comprising a wireless receiver connected to and powered by the powersupply 30 within a control circuit. The enclosure 24 not only serves tohouse these electronic components in a safely enclosed environment, butalso doubles as a support for components of a magnetic hold/releasemechanism by which the selected drop pan can be normally maintained in anested position disposed at least partially within the interior space 22of the support housing 12.

This magnetic hold/release mechanism comprises a pair ofelectro-permanent magnets 34 protruding downwardly from the bottomenclosure wall 28 toward, but stopping short of, the lower planeoccupied by the housing's open bottom. In a known manner, anelectro-permanent magnetic is operable to switch between a defaultholding state exerting an external magnetic field, and a release statelacking said external magnetic field. The default holding state consumesno electrical power, and thus is also referred to herein as ade-energized state of the electro-permanent magnet, while the releasestate requires application of DC power to an electrical coil of theelectro-permanent magnet, and is therefore also referred to herein as anenergized state of the electro-permanent magnet. To enable control overthe state of the electro-permanent magnets, the control circuitcontaining the wireless transmitter is also connected to the electricalcoil of each electro-permanent magnet, and is configured to switchbetween an “off” state electrically isolating the power supply from thecoils of the electro-permanent magnets, and an “on” state electricallyconnecting the power supply to the coils electro-permanent magnets. Thecontrol circuit is configured to maintain the “off” state by default. Inresponse to a command signal sent to the receiver from the transmitterof a wireless remote control 36, whether operated by the driver of thecombine harvester or other personnel in the proximity thereof, thecontrol circuit momentarily switches to the “on” state, thus deliveringa momentary pulse of current from the power supply to the coils of theelectro-permanent magnets to switch them from the holding state to therelease state. After holding the closed state of the circuit for thepredetermined pulse length, the circuit automatically returns to theopen state, and remains in such state until a subsequent command signalis received.

In order to be magnetically attractable to the electro-permanentmagnets, the drop pans 14A, 14B may be made entirely or partially offerromagnetic material. Another possible construction employs anon-ferromagnetic substance as its constituent material making up themajority of each pan, for example defining a floor and surroundingperimeter walls thereof, while adding smaller ferromagnetic pieces 38suitably positioned on the pans for alignment with the electro-permanentmagnets during nested placement of the selected drop pan into thehousing 12. In another example, ferromagnetic steel is used as theconstituent material (e.g. aluminum, plastic, composites, etc.) makingup the floor and perimeter walls, which are then painted or powdercoated, and the smaller ferromagnetic pieces subsequently added to thepainted/coated constituent parts are not painted or powder coated withthe same material or thickness of paint or other coating t, which maydetriment their magnetic attractiveness, though other chemicaltreatments or coatings of different material composition or thicknessmay used to still provide corrosion protection while being of lessmagnetic detriment. In the illustrated embodiment, each ferromagneticpiece 38 is a flat steel plate fastened to a topside of the pan's bottomfloor 40.

In the illustrated embodiment, the bottom floor 40 of each pan is ofelongated rectangular shape slightly shorter and narrower than the topwall 16 and open bottom of the housing 12, and the perimeter walls ofeach pan thus include longitudinally oriented front and rear pan walls42 of greater length than shorter left and right pan walls 44 thatinterconnect the front and rear pan walls at opposite ends thereof. Thefront and rear pan walls are outwardly sloped to diverge upwardly awayfrom the bottom floor of the pan. The left and right pan walls aretrapezoidally shaped to fully close off the ends of the pan between thesloped front and rear walls thereof. Each pan has a rectangular open topdelimited between the front, rear, left and right pan walls at the topends thereof in an upper plane of the pan situated oppositely of andparallel to the bottom floor 40. The open top of each pan is slightlyshorter and narrower than the top wall 16 and open bottom of the housing12, whereby the pan, or least the open top thereof, is insertableupwardly into the housing 12 through the open bottom thereof for nestedreceipt of the pan at least partially within the interior space of thehousing. Preferably the height of each pan is less than that of thehousing to enable full receipt of the entire pan within the interiorspace 22 of the housing 12 so that the bottom floor 40 of the panresides within or slightly above the lower plane of the housing 12 inthe pans fully nested position therein.

The interior space 22 of the housing 12 features identical left andright guide brackets 46 situated respectively adjacent the left andright housing walls 18 in parallel relation thereto at short distancesinward therefrom. Each guide bracket 46 in the illustrated embodiment isa flat plate lying parallel to its adjacent one of the left and righthousing walls. A flat top edge of each guide bracket 46 is affixed tothe underside of the housing's top wall 16, while the bracket's bottomedge follows a non-linear path giving the bracket a variable-heightprofile from one end of the bracket to the other. Each bracket 46 issymmetric across the longitudinal mid-plane P, and the variable-heightprofile divides each bracket 46 into three distinguishable lobes, namelya center lobe 48 situated on and bisected by the mid-plane P, and twoouter lobes 50 situated on opposite sides of the center lobe insymmetric relation to one another across the mid-plane P.

The center lobe 48 is trapezoidal in shape, being delimited byconvergently sloped edges 48 a that converge downwardly toward themid-plane P from opposite sides thereof, and are joined together acrosssaid mid-plane by a flat central edge 48 b lying parallel to the topwall 16 of the housing. The angle of convergence between these slopededges 48 a of the bracket's central lobe matches the angle at which thesloped front and rear walls of the smaller drop pan 14A convergedownwardly toward the floor of the drop pan 14A.

Each outer lobe 50 is delimited between an inwardly sloped outer edge 50a that slopes downwardly toward the mid-plane P from near the front orrear housing wall 18, an opposing inner edge 50 b facing the nearestsloped edge 48 a of the central lobe across a gap G left therebetween,and a bottom edge 50 c joining together the inner and outer edge of theouter lobe in generally parallel relation to the top wall 16 of thehousing 12. The sloped outer edges 50 a of the two outer lobes thusconverge downwardly and symmetrically toward the mid-plane. The angle ofconvergence between these outer edges 50 a matches the angle at whichthe sloped front and rear walls of the larger drop pan 14B convergedownwardly toward the floor of the drop pan 14B. The distance betweenthese outer edges 50 a where they meet the bottom edges 50 c of theouter lobes closely matches the bottom width of the larger drop pan 14B,as measured across the floor of the larger drop pan 14B between thebottom ends of the front and rear pan walls thereof. Likewise, thedistance between the outer edges 50 a of the outer guide bracket lobesnear the top wall 16 of the housing 12 closely matches the top width ofthe larger drop pan 14B, as measured across the open top of the largerdrop pan 14B between the top ends of the front and rear pan wallsthereof. The bottom edges 50 c of the outer lobes lie in or slightlyabove the same plane as the bottom ends of the electro-permanent magnets34.

The trapezoidal center lobes 48 of the two guide brackets 46 cap off thetwo longitudinally opposing ends of the enclosure 24 in which thehousing's electronic components are housed. The electro-permanentmagnets 34 are mounted to the bottom enclosure wall 28 and are centeredon the mid-plane P at positions respectively near the two guide brackets46 at the ends of the enclosure 24.

Since the downwardly converging trapezoidal shape shared by the centerlobes 48 of the two brackets 46 is centered on the same mid-plane P inwhich the electro-permanent magnets 34 are mounted, and the taper orconvergence angle of these center lobes 48 matches that of the smallerdrop pan 14A, the sloped edges 48 a of the central lobe form guidesurfaces for centering the bottom wall of the smaller drop pan on themid-plane of the housing to thereby align the floor of the smaller droppan 14A with the electro-permanent magnets 34. Manually lifting thesmaller drop pan upwardly into the open bottom of the support housing 34brings the ferromagnetic pieces 38 on the floor 40 of the pan 14A intoproximity with the electro-permanent magnets 34. Accordingly, as long asthe drop pan 14A is generally centered enough so that its open top endencompasses the bottom edge 48 b of the guide bracket center lobes, thedrop pan 14A will self-center itself on the midplane P as the externalmagnetic field exerted by the default holding state of theelectro-permanent magnets 34 lifts the ferromagnetic pieces 38 on thepan floor 40 upwardly into contact with the bottom ends of theelectro-permanent magnets 34. The center lobes 48 of the two guidebrackets 46 thus define an inner set of alignment guides for guidedself-alignment of the smaller drop pan 14A during magnetically aidedlifting of the drop pan into a nested position inside the supporthousing 12, during which the gaps G between the center lobe 48 of eachbracket and the outer lobes 50 thereof accommodate the front and rearpan walls 42 of the smaller pan 14A.

Similarly, since the downward convergence of the outer edges 50 a of theouter lobes 50 of each bracket is centered on the same mid-plane P inwhich the electro-permanent magnets 34 are mounted, and matches thetaper or convergence angle between the front and rear walls 42 of thelarger drop pan 14B, the outer edges 50 a of the outer lobes 50 of thetwo brackets 46 form guide surfaces for centering the bottom wall 40 ofthe larger drop pan 14B on the mid-plane P of the support housing 12 tothereby align the floor 40 of the larger drop pan 14B with theelectro-permanent magnets 34. Manually lifting the larger drop panupwardly into the open bottom of the support housing 12 brings theferromagnetic pieces 38 on the floor 40 of the pan into proximity withthe electro-permanent magnets 34, and as long as the drop pan isgenerally centered enough that its open top end encompasses the bottomedges 50 c of the outer guide bracket lobes 50, the drop pan willself-center itself on the midplane P as the magnetic field exerted bythe default holding state of electro-permanent magnets 34 lifts theferromagnetic pieces 38 on the pan floor 40 upwardly into contact withthe bottom ends of the electro-permanent magnets 34. The outer lobes 50of the two guide brackets 46 thus define an outer set of alignmentguides for self-alignment of the larger drop pan 14B during magneticallyaided lifting thereof into the nested position inside the supporthousing 12.

While the inner and outer alignment guides near each end of the housingare integrally seamless parts of a singular unitary bracket in theillustrated embodiment, where the gaps G open upwardly into the bracketbut stop short of the mounted upper edge thereof where intact upperportions of the bracket join the different lobes together, it will beappreciated that discrete and separate lobes individually defined byrespective individual pieces may be employed instead of integrallyconnected lobes of a common bracket. The smaller drop pan, having alesser with than the larger drop pan, is better suited than the largerdrop pan for use in long stubble conditions, for example when harvestingcanola or hemp, during which relatively tall stubble is left behind inthe field compared to wheat or other shorter stubble crops. In such longstubble conditions, wider drop pans have a greater likelihood of tippingover as they fall to the ground due to interference by the tall stubble.The top width of the smaller drop pan at the open top end thereof ispreferably less than eight inches, and less than six inches in someembodiments. Among select embodiments, the top width may be betweenthree and five inches, and approximately four inches in one particularembodiment. This reduced width falls more easily between adjacent stalksof tall stubble, thus reducing the likelihood of tipping, and therebypreventing loss of the collected sample.

As best shown in FIG. 6, to help resist tipping, the larger drop pan 14Bhas out-turned wings 56 extending outwardly therefrom in downwardly andoutwardly sloping relation from the top ends of the front and rear walls42 of the pan. As shown, these wings 54 may be formed by integrally bentupper portions of the front and rear walls. As can be seen in FIGS. 1and 2, the wings 56 preferably span a full or near entirety of the frontand rear walls in the longitudinal direction of the pan. These wingshelp stabilize the wider pan atop or in the stubble to help reduce thechance of tipping.

To mount the support housing 12 to the undercarriage of a combineharvester, for example to the underside 100 a of an axle housing 100 ofthe combine harvester's rear wheels 102 thereof as shown in FIG. 5, amagnetic mounting arrangement features a pair of permanent magnets 52situated above top wall 16 of the housing in spaced elevation therefromatop a pair of risers 54. The use of permanent magnets allows tool freemounting of the support housing to any combine harvester without anymodifications thereto, and without the energy consumption associatedwith electromagnet retention of the housing. The use ofelectro-permanent magnets for the magnetic retention of the drop panalso reduces energy consumption by energizing the coils of theelectro-permanent magnets only momentarily to switch from the holdingstate to the release state, and only in response to the command signalfrom the remote control when the operator wishes the release the droppan from the moving combine harvester. Also, by using the supporthousing to indirectly carry the drop pan on the combine harvester, therequired strength of the electro-permanent magnets is reduced, as theweight of the power supply, control circuit and electro-permanentmagnets is borne by the permanent magnets 52 that hold the housing tothe combine harvester, not by the electro-permanent magnets.

With the reduced power requirements of the system, the relatively smallpower supply, preferably consisting of only a singular battery, has alesser width and depth than the smaller drop pan, and is placed in themiddle area of the drop pan between the alignment brackets 46 in asimilarly narrow enclosure 24 so that the enclosure the power supplycontained therein fit within the footprint of either selected one of thedrop pans when nested within the support housing. This helps keep theoverall size of the support housing to a minimum by avoiding the need toextend the length or width of the support housing notably beyond the panlength or width in order to accommodate space for a larger battery orlarger group of batteries that would have to be placed outside thefootprint occupied by either drop pan. Additionally, with the drop pan,or at least the open top end thereof, situated within the interior spaceof the support housing, the top end of the drop pan is fully shielded bythe support housing to prevent inadvertent admission of material intothe drop pan before being dropped to the ground in response to thecommand signal from the wireless remote control.

While the forgoing embodiments are described primary in the context oftesting the performance of a combine harvester, the same system be usedon other conveyed machines or implements, whether self-conveyed ortowed, to collect samples of material being discharged therefrom to theunderlying ground surface over which the machine or implement isconveyed. For example, the system may be used to collect dischargesamples from lime and compost spreaders to enable assessment andcalibration of the machine's operational characteristics.

FIGS. 7 through 10 illustrate a separator unit 60 operable forseparating grain kernels from straw and chaff in a grain loss samplecollected from a drop pan, whether from the above described drop pansystem of the present invention, or another known drop pan system, forexample of the types described in the forgoing background. The separatorfeatures a container 62 having a cylindrically shaped peripheral wall 63standing upright from a flat circular floor 64 of the container around afull perimeter thereof to delimit an interior space of the container 62above the floor 64 and within the confines of the peripheral wall 63.Within the interior space of the container, a rechargeable battery 66 ismounted atop the floor 64 and held in a static position thereon by abattery hold-down 68 that resides in embracing relation over the batteryand is fastened to the container floor 64. A charging cable 70 reachesoutward from the battery 66 to a charging port 71 in the peripheral wall63 of the container to enable recharging of the battery 66 by connectionto an external charger (not shown). The charging cable may incorporatesuitable fuse protection between the battery and charging port.

The container features an open top end 72 through which the grain losssample from the drop tray can be poured into the container. Within theinterior space of the container at a spaced elevation below the open topend 72, a mesh screen 74 divides the interior space of the containerinto an upper sample-receiving compartment 62 a situated above thescreen for receiving the grain sample, and a lower component-housingcompartment 62 b situated below the screen for housing operationalcomponents of the separator, including the aforementioned rechargeablepower supply. A variable speed fan 76 forms another operationalcomponent of the separator unit, specifically a variable speed airmoving device for blowing air upwardly through the mesh screen 74 intothe upper sample-receiving compartment 62 a, and onward through the opentop end 72 of the container. The fan housing 78 is thus mounted belowthe mesh screen 74 and above the rechargeable battery 66, with theairflow outlet 78 a of the fan housing 78 facing upwardly toward theopen end 72 of the container.

At the lower component-housing compartment 62 b of the container 62, theperipheral wall 63 has a series of air intake openings 80 situatedtherein at regularly spaced intervals therearound to provide a source ofambient intake air to the variable speed fan 76 from outside thecontainer 62. As shown, these air intake openings may be in form ofelongated slots lying axially of the container 62 to reach upwardlytoward the fan from near the container floor 64. The upper portion ofthe peripheral wall 63 surrounding the upper sample-receivingcompartment 62 a is of solid unperforated construction. This forms asolid shroud that surrounds this upper compartment 62 a and standsupright from the mesh screen 74 around the full circumference thereof sothat all upward airflow from the fan 76 through the mesh screen 74 canonly exit container through the open top end thereof 72, thus liftingthe freed chaff upwardly therethrough to exit the container 62.

An on/off control 76 and a speed selection control 78 are mounted to theperipheral wall 63 of the container at the lower component-housingcompartment 62 b thereof and accessible at the exterior of theperipheral wall 63 to receive selective control input from a userconcerning operation of the fan 76. For such purposes, these controls76, 78 are thus wired in a control circuit with the rechargeable battery66 and the variable speed fan 76 to control operation thereof. Theon/off control 76, for example a push button or toggle switch, isoperable to selectively activate and deactivate the fan by making andbreaking an electrical connection in the control circuit between the fanand the power supply, while the speed selection control 78, for examplefeaturing a rotational knob or dial, is operable to vary the rotationalspeed of the fan blades and thereby control the the rate of airflowforced upwardly thereby through the mesh screen, for example byadjusting an applied voltage level to the fan or adjusting the pulsewidth of a pulse wave modulation (PWM) signal from the battery to thefan. Such fan speed control techniques are well known and easilyimplemented using commercially available fan speed controllers, and thusare not described in further detail herein. Since known commerciallyavailable components can be used for the on/off and speed controls, theyare illustrated only schematically and without detail.

As an alternative to an electronic speed controller of a variable speedfan, the airflow control mechanism for changing the airflow rate throughthe mesh screen may instead take the form of a mechanical device, forexample an airflow restrictor movable into different positions ofvarying alignment with the air intake openings 80 of the container tocontrol the admission of ambient air into the container, thuscontrolling the supply of intake air to the fan. This restrictor maytake the form of a curved plate situated internally or externally of thecontainer and movable into and out of a position partially obstructingthe air intake openings in order to reduce the flow of intake air intothe container during operation of the fan, thereby reducing the forcedair flow rate through the mesh screen. In one embodiment, the restrictorhas control openings therein that are laid out in similar or matchingpattern to the air intake openings 80, whereby the restrictor is movablearound the central longitudinal axis of the container between an openposition aligning the control openings with the air intake openings 80to leave the airflow openings completely unobstructed for maximum intakeairflow, and a partially closed position placing the control openings inoverlappingly offset relation to the intake openings 80 to partiallyobstruct the air intake openings 80 and thereby reduce airflow into thecontainer and through the mesh screen.

The variable speed operability of unit provides improved flexibilityover the prior art, as the ability to control the operating speed of theair moving device improves compatibility with a wider variety of crops.For crops whose grain kernels are of lesser weight and/or greatersurface area, a lower speed setting of the fan is selected to ensurethat the grain kernels are not blown upwardly off the screen and throughthe open top end of the container with the chaff. Crops whose grainkernels are of greater weight and/or lesser surface area can beseparated using a higher fan speed to ensure thorough separation withreduced risk of the grain kernels being discharged with the separatedchaff being blown out through the open top end of the separator. Suchdifferences in weigh concentration can be due to different crop types,different moisture levels within the same crop type, or other cropcharacteristics or attributes.

As shown in the cross-sectional view of FIG. 10, the mesh screen 74 maybe stretched across the central opening of a peripheral rim 82, which inturn is fastened atop a screen support rim 84 a having downturnedmounting tabs 84 b fastened to the inside of the container's peripheralwall 63 at spaced positions therearound. Likewise, the fan housing 78may be attached to the underside of a fan support rim 86 a havingdownturned mounting tabs 86 b fastened to the inside of the container'speripheral wall 63 at spaced positions therearound.

As also shown in the drawings, the separator unit 60 may feature a bailhandle 88 having its opposite ends pivotally pinned to the peripheralwall 63 of the container 62 at diametrically opposite points near theopen top end 72 thereof for selective pivoting of the handle between astowed position suspended at the side of the container, as shown in thedrawings, and a deployed working position spanning diametrically acrossthe open top end of the container at a spaced elevation thereabove. Thecontainer is thus conveniently and comfortably carried in a bucket-likefashion with the container freely swinging from the manually grippedhandle in a generally upright position thereunder. While the illustratedembodiment features a cylindrical container of circular cross-sectionabout its longitudinal axis, the cross-sectional shape of the containermay be varied without departure from the present invention, and may, forexample, be square in cross-section.

Since various modifications can be made in my invention as herein abovedescribed, and many apparently widely different embodiments of samemade, it is intended that all matter contained in the accompanyingspecification shall be interpreted as illustrative only and not in alimiting sense.

1. A drop pan system for collecting a discharge sample from a conveyedmachine or implement that discharges material to a ground surface overwhich the machine or implement travels, said system comprising: asupport housing attachable to the machine or implement; a drop panreceivable in a nested position at least partially within said housing;a magnetic hold/release mechanism comprising at least oneelectro-permanent magnet responsive to selective energization to switchfrom a holding state emitting an external magnetic field for holding thedrop pan in the nested position, to a release state cancelling saidexternal magnetic field to thereby release the drop pan from thehousing; a power supply supported on the housing; a control circuitbetween the power supply and the magnetic hold/release mechanismoperable to make and break an electrically conductive connectiontherebetween; and a remote control transmitter communicable with areceiver in the control circuit to effect switching of said controlcircuit from an open state in which the magnetic hold/release mechanismis de-energized, to a closed state in which the magnetic/hold releasemechanism is energized.
 2. The drop pan system of claim 1 wherein thepower supply is positioned to reside within a footprint of the droppan's nested position inside the housing.
 3. The drop pan system ofclaim 1 wherein the power supply is positioned within an enclosure,which doubles as a support for one or more components of the magnetichold/release mechanism.
 4. The drop pan system of claim 3 wherein thehousing comprises a top wall and a plurality of peripheral wallsdepending from said top wall around a perimeter thereof to delimit aninterior space of the housing in which the drop pan is nestable throughan open bottom of said housing, the enclosure comprises a bottom wallresiding in spaced relation from the top wall of the housing, the powersupply resides between said top wall of the housing and said bottom wallof the enclosure, and at least one electro-permanent magnet of themagnetic hold/release mechanism protrudes externally from said bottomwall of the enclosure and downwardly away from the top wall of thehousing.
 5. The drop pan system of claim 3 wherein said enclosure runslongitudinally of the housing and the magnetic hold/release mechanismcomprises two electro-permanent magnets disposed at spaced apartpositions adjacent opposing ends of said enclosure.
 6. A drop pan systemfor collecting a discharge sample from a conveyed machine or implementthat discharges material to a ground surface over which the machine orimplement travels, said system comprising: a housing attachable to themachine or implement; a set of differently sized drop pans, each droppan being selectively receivable in a nested position at least partiallywithin the housing; a hold/release mechanism operable between a holdingstate holding the drop pan in the nested position and a release statereleasing the drop pan from the housing; and alignment guides forselectively aligning any selected one of said differently sized droppans relative to the housing and the hold/release mechanism duringnested placement of said selected one of said differently sized droppans in said housing.
 7. The drop pan system of claim 6 wherein saidalignment guides comprise an inner set of guides for receiving walls ofa smaller one of said differently sized drop pans and an outer set ofguides for receiving walls of a larger one of said differently sizeddrop pans.
 8. The drop pan system of claim 7 wherein each set of guidescomprises convergently sloped guide surfaces that converge in a downwarddirection toward an open bottom of the housing, and each drop pancomprises a pair of convergently sloped walls that converge in thedownward direction toward a closed bottom of the drop pan.
 9. The droppan system of claim 7 wherein the outer set of guides comprise guidelobes situated on opposite sides of said inner set of guides.
 10. Thedrop pan system of claim 9 comprising at least one guide bracketdefining both an inner guide an inner guide for the smaller one of saiddifferently sized drop pans and an outer guide for the larger one ofsaid differently sized drop pans, said outer guide comprising a pair ofouter guide lobes situated on opposite sides of said inner guide anddistinguished therefrom by gaps in said guide bracket.
 11. The drop pansystem of claim 10 wherein said at least one guide bracket comprises twoguide brackets residing respectively adjacent opposite ends of thehousing.
 12. The drop pan of claim 6 wherein the guides include at leastone guide positioned to cap off a respective end of an enclosure thathouses one or more electronic components for controlling thehold-release mechanism.
 13. The drop pan system of claim 6 wherein anarrower one of said differently sized drop pans has a width of lessthan eight inches.
 14. The drop pan system of claim 6 wherein a narrowerone of said differently sized drop pans has a width of less than sixinches.
 15. The drop pan system of claim 6 wherein a narrower one ofsaid differently sized drop pans has a width of between three and fiveinches, inclusive.
 16. A drop pan system for collecting a dischargesample from a conveyed machine or implement that discharges material toa ground surface over which the machine or implement travels, saidsystem comprising: a drop pan; and a hold/release mechanism operablebetween a holding state holding the drop pan in a carried position onthe machine or implement and a release state releasing the drop pan fromthe machine or implement; wherein said drop pan is characterized by oneor more of the following features: (a) said drop pan has a width of lessthan 8-inches; and/or (b) said drop pan has out-turned wings extendingoutwardly from perimeter walls thereof.
 17. The drop pan system of claim16 characterized by inclusion of feature (a).
 18. The drop pan system ofclaim 17 characterized by inclusion of feature (b).
 19. A drop pansystem for collecting a discharge sample from a conveyed machine orimplement that discharges material to a ground surface over which themachine or implement travels, said system comprising: a housingattachable to the machine or implement; a drop pan selectivelyreceivable in a nested position at least partially within the housing; amagnetic hold/release mechanism operable between a holding state holdingthe drop pan in the nested position and a release state releasing thedrop pan from the housing; wherein said drop pan system is furthercharacterized by one or more of the following: (a) the housing comprisesan enclosure that houses one or more electronic components for operatingthe hold-release mechanism, and that doubles as a support on whichmagnetic components of the magnetic hold/release mechanism aresupported; and/or (b) a power supply is supported on the housing forpowering the magnetic hold/release mechanism, and said power supply ispositioned at an area of said housing that resides within a footprint ofthe drop pan's nested position inside the housing.
 20. The drop pansystem of claim 19 characterized by inclusion of feature (a).
 21. Thedrop pan system of claim 19 characterized by inclusion of feature (b).22. A grain loss sample separator for separating grain kernels fromstraw and chaff in a grain loss sample, said grain sample separatorcomprising: a screen atop for receiving said grain sample thereatop; andan air moving device operable to force air upwardly through said screento thereby blow away said straw and chaff while leaving said grainkernels to settle atop the screen; and an airflow control mechanismhaving multiple air speed settings selectable by a user to adjust anairflow speed through said screen according to crop characteristics ofsaid grain loss sample.
 23. The grain loss sample separator of claim 22wherein said air moving device is a fan and said airflow controlmechanism is a fan speed controller by which selection of the air speedsettings changes an operating speed of said fan.